Electric Submersible Pump Service Truck

ABSTRACT

A self propelled or trailer frame is provided with a cradle on which the tool for subterranean use can be assembled preferably in a shop protected from the weather. The tool is transported to a well site and the truck is positioned for deployment. The cradle is on a sub-frame that can translate off the end of the truck bed to get an end of the tool closer to the wellhead. The truck has a hydraulic linkage to upend the nearest end to the wellhead to a point close to where a hook in a derrick that is over the wellhead can be attached to the tool for hoisting the tool up so as to lift it off the cradle with minimal side loading on the derrick as the tool lower end leaves the cradle. The tool can be an electric submersible pump and can be used for delivery as well as removal of the tool through a wellhead.

FIELD OF THE INVENTION

The field of the invention is service vehicles for land based wells andmore particularly vehicles that allow the assembly and placement ofelectric submersible pumps in position for insertion or removal from asubterranean location.

BACKGROUND OF THE INVENTION

Self propelled and trailer service vehicles designed to be placed near awellhead and having a tilt up derrick have long been in use to servicewells in certain circumstances. These derrick structures pivot intoposition over the cab or off the rear of the vehicle whether selfpropelled or a trailer. Some examples of such designs are U.S. Pat.Nos.: 4,591,006; 4,743,175; 4,901,805; 5,174,389; 5,524,716; 5,711,382;5,931,238; 6,003,598; 6,530,432; 7,111,689 and 7,249,629. U.S. Pat. No.4,981,080 shows a pipe carrier on wheels to go into a larger access pipeand carry a submersible pump to deliver fluids that flow into thecollection pipe to a remote storage tank.

Electric submersible pumps (ESP) are long assemblies designed to bedelivered to a subterranean location for deployment in wells that needto be pumped to remove hydrocarbons from formations where the pressurein the formation will not bring the hydrocarbons to the surface. Suchpump assemblies are made of components such as the pump section, themotor and an instrument housing. Typically these segments are brought tothe well site and assembled together in a derrick that is already thereover the wellhead. The assembly process has to take place at elevatedlocations in the derrick and frequently in harsh climates. Not only arethere safety issues with this procedure but such assembly procedures atthe well site are expensive and take time thus delaying resumption orinitiation of production.

The present invention addresses such issues by allowing the ESP to beassembled in a cradle that is on a self propelled truck or on a trailer.The ESP can be retained in such a cradle for over the road transport tothe well site. At the well site the cradle can be translated off an endof the vehicle to get it closer to the wellhead from the point where thevehicle cannot get any closer. The ability to bring the cradle back withthe assembled ESP then facilitates getting a end of the assembled ESPhooked to a travelling block or hoist already in the derrick over thewellhead so that the hook can be attached to allow the hook to furtherlift the ESP from the cradle for ultimate alignment with the wellhead inthe derrick. The ability to extend the cradle before tilting towardvertical reduces the lateral forces on the derrick as it assumes theweight of the ESP after the hook is attached and as the ESP comes offthe cradle. The vehicle can be used to deliver or remove an ESP or anyother tool with respect to the wellhead. These and other features willbe more apparent to those skilled in the art from a review of thedetailed description and the associated drawings while recognizing thatthe claims determine the full scope of the invention.

SUMMARY OF THE INVENTION

A self propelled or trailer frame is provided with a cradle on which thetool for subterranean use can be assembled preferably in a shopprotected from the weather. The tool is transported to a well site andthe truck is positioned for deployment. The cradle is on a sub-framethat can translate off the end of the truck bed to get an end of thetool closer to the wellhead. The truck has a hydraulic linkage to upendthe nearest end to the wellhead to a point close to where a hook in aderrick that is over the wellhead can be attached to the tool forhoisting the tool up so as to lift it off the cradle with minimal sideloading on the derrick as the tool lower end leaves the cradle. The toolcan be an electric submersible pump and can be used for delivery as wellas removal of the tool through a wellhead.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the trailer in the over the road position;

FIG. 2 shows the trailer with the boom tilted and the subframe pulledalong the boom with a separate hook at the well site so as to get thetool as close to vertical as possible before removal of the tool fromthe subframe.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a trailer 10 with a wheel assembly 12 near the rear end 14.Spaced apart booms 16 and 18 are mounted on the trailer 10 to assist inassembly of the components of an ESP 20 on a carriage 22. Carriage 22has a leading end 24 and a trailing end 26. Carriage 22 is supportedfrom a subframe 30 and can be lifted at the leading end 24 by a hook 32that is supported by a truck mounted derrick, not shown, or some othersupport structure that is provided over the wellhead, also not shown.Carriage 22 can roll along the subframe 30 such as on a wheel assembly28. The ESP 20 can be initially assembled onto the carriage 22 using thebooms 16 or 18 or other lifting equipment and secured to the carriagefor over the road transport.

The subframe 30 is mounted on a base frame 34 that is in turn supportedoff the truck bed 36. A hydraulic linkage 38 can tilt the subframe 30 byurging its trailing end 26 to slide along the base frame 34 using asliding member 40 whose shifted position can be seen in FIG. 2 with thelinkage 38 having extended to raise the connection point 42. In thismanner the subframe 30 is maintained in a stable position with respectto the trailer 10 as it is secured at the sliding member 40 and atconnection point 42 while tilted into the FIG. 2 position.

It is while the ESP 20 is in the subframe 30 and in the FIG. 2 positionthat the hook 32 is attached to the ESP 20, which at that time is stillsecured to the carriage 24. As a lifting force is applied by the hook 32the ESP 20 and the carriage 24 move in tandem and the rear 26 of the isretained to the carriage 24 which glides on subframe 30 that has stoppedmoving as linkage 38 has moved to its travel limit. With rollers 28secured to the subframe 30, the carriage 24 can then tilt up under thepulling force of the hook 32 as the carriage 24 and the ESP 20 approacha nearly vertical position. At that time the ESP while supported fromthe hook 32 is released from the carriage 24. At this point there is notmuch of a swinging momentum to the ESP as it is nearly vertical. Thecarriage 24 can be supported off the subframe with a hydraulic dampener25, shown schematically in FIG. 2, that allows it to slowly descend, butwhich does not retard movement when the carriage 24 is lifted by thehook 32, when the carriage 24 is released from the ESP 20 that is nowsupported solo by the hook 32. Preferably, the ESP 20 is allowed toswing through the carriage 24 to reach a vertical position over thewellhead. Alternative designs can also reposition the ESP off eitherside of the carriage 24 to allow it to go into a vertical position.After the ESP 20 is off the carriage 24 the carriage 24 is slowlybrought down to the still inclined subframe 30. Upon landing in thesubframe 30, the hydraulic system linkage 38 is activated to lower thesubframe 30 back down to the base frame 34. The trailer 10 is then readyto go over the road.

Those skilled in the art will realize that an ESP can be delivered to asite fully assembled and picked up and lowered into a wellbore as anassembly. The reverse is also possible using this equipment.

As an option the base frame 34 can be mounted to translatelongitudinally with respect to the truck bed 36 to allow a closerapproach to the wellhead than would otherwise be allowed with thetrailer 10. While a trailer 10 is illustrated, the described assemblycan be a part of a self propelled vehicle such as a straight truck.While an ESP is contemplated to be used with such a service vehicle,those skilled in the art will appreciate that other types of downholeequipment can be used without departing from the scope of the invention.

When installing an ESP, the assembly can be built onto the carriage 24inside a shop and out of the weather and delivered to a site as anassembly for installation. Field assembly of the ESP components is nolonger required. With the ability to tilt the carriage 24 with respectto the already inclined subframe 30 the handling of the assembled ESP issimplified due to the ability to get the ESP closer to vertical beforelifting it off the carriage 24. As a further option the base frame 34can be mounted to translate toward the well to get the end of the ESPthat is being picked up that much closer to the well to allow for asafer repositioning of the ESP from the carriage 24 to a supportedvertical position over the wellhead.

The above description is illustrative of the preferred embodiment andmany modifications may be made by those skilled in the art withoutdeparting from the invention whose scope is to be determined from theliteral and equivalent scope of the claims below.

1. A service vehicle assembly for delivery or removal of tools withrespect to a subterranean location using a lifting device located at thesurface, comprising: a carriage for supporting a tool thereon, saidcarriage mounted to a frame assembly, said frame assembly supported onthe service vehicle for selectively moving said carriage with respect tothe vehicle; said carriage movable with respect to said frame assemblyafter movement in tandem with said frame assembly.
 2. The assembly ofclaim 1, wherein: said carriage comprises a leading end that can bemoved away from said frame assembly by the lifting device while atrailing end is movably retained to said frame assembly.
 3. The assemblyof claim 1, wherein: said carriage can translate relative to said frameassembly while still retained to said frame assembly.
 4. The assembly ofclaim 3, wherein: said carriage can tilt away from said frame assemblyas at least a portion of said carriage translates along said frameassembly.
 5. The assembly of claim 4, wherein: said carriage has atleast one roller adjacent an end thereof that retains said carriage tosaid frame assembly as that end translates along said frame assembly. 6.The assembly of claim 5, wherein: said frame assembly comprises a baseframe and a sub frame movable with respect to said base frame that issupported by the service vehicle.
 7. The assembly of claim 6, wherein:said subframe is tilted with respect to said base frame by ahydraulically powered linkage.
 8. The assembly of claim 4, wherein: saidcarriage tilts away from said frame assembly when the tool that issecured to said carriage is lifted by the lifting device.
 9. Theassembly of claim 8, wherein: said frame assembly comprising a let downmechanism to allow said carriage to descend to said frame assembly whenthe tool is released from the carriage while the tool is still supportedby the lifting device.
 10. The assembly of claim 4, further comprising:an electric submersible pump assembly ready for subterranean use andmounted to said carriage.
 11. The assembly of claim 10, wherein: saidcarriage can translate relative to said frame assembly while stillretained to said frame assembly.
 12. The assembly of claim 11, wherein:said carriage can tilt away from said frame assembly as at least aportion of said carriage translates along said frame assembly.
 13. Theassembly of claim 12, wherein: said carriage has at least one rolleradjacent an end thereof that retains said carriage to said frameassembly as that end translates along said frame assembly.
 14. Theassembly of claim 13, wherein: said frame assembly comprises a baseframe and a sub frame movable with respect to said base frame that issupported by the service vehicle.
 15. The assembly of claim 14, wherein:said subframe is tilted with respect to said base frame by ahydraulically powered linkage.
 16. The assembly of claim 12, wherein:said carriage tilts away from said frame assembly when the tool that issecured to said carriage is lifted by the lifting device.
 17. Theassembly of claim 16, wherein: said frame assembly comprising a let downmechanism to allow said carriage to descend to said frame assembly whenthe tool is released from the carriage while the tool is still supportedby the lifting device.